function [I] = readImage( str )
	filename = ['E:\Fun\SeniorThesis\images\gray\', str];
	f = double(imread(filename));
	if length(size(f)) == 2
		I = f;
	elseif length(size(f)) == 3
		I = shiftdim(f,2);
	end
	I = (I - min(I(:))) / (max(I(:))-min(I(:)));
end 